Air conditioning distributor unit



J. W. KREUTTNER AIR CONDITIONING DISTRIBUTOR UNIT April 7, 1959 2 Sheets-Sheet 1 Filed April 23, 1953 INVENToR. JZH/B WWU/TAE? April 7, 1959 J. W. KREUTTNER AIR CONDITIONING DISTRIBUTOR UNIT Filed April' 23, 1955 2 Sheets-Sheet 2 BYfMM/M United States Patent() AIR CONDITIONING DISTRIBUTOR UNIT 'Joseph W. Kreuttner, North Tarrytown, N.Y., assgnor l -to Buensod-Stacey, Incorporated, New York, N.Y., a

corporation of Delaware Application April 23, 1953, Serial No. 350,554

Claims. (Cl. 137-111) This invention relates to air conditioning apparatus and more particularly to improved damper arrangements for air distributing units used in air conditioning :systems vthat treat warm and cold air separately and mix such air prior to distribution in Zones being conditioned.

Such air conditioning systems are extremely well suited for regulating individual room temperatures. A `material objection, however, has been the audible noises which have heretofore accompanied the operation lof the distributing units, particularly where air is supplied under high pressure. Such noises are especially pronounced when flow conditions in the system are upset to satisfy temperature demands in the zones.

It is, therefore, an object of this invention to provide simple and compact damper arrangements which eliminate objectionable noise in the operation of such distributing units.

' Another object of this invention is to provide an efficient condition-responsive arrangement for selectively proportioning warm and cold air and for automatically maintaining constant volume delivery of conditioned air into a zone.

A further object of the invention is to provide an improved distributing system for delivering air iu substantially equal and constant volume to every zone in the system.

. The present damper arrangement both proportions the amounts of warm and cold air and determines total volume of air admitted. The present device is particularly adapted for use in distributing units in which air is delivered into an air mixing chamber through side wall apertures of a sleeve which communicates at opposite ends with warm and cold air supply ducts. The device includes a pair of dampers carried and actuated by a single, motoroperated plunger, the dampers being movable linearly in the apertured sleeve between a position closing the warm air supply duct and fully opening the cold air supply duct and a position closing the cold air supply duct and fully opening the warm air supply duct. The dampers are so mounted on the plunger so as to be moved in unison and to cooperate with the side wall apertures to proportion and admit air from the air supply ducts, the positions of the dampers in the duct determining the proportional amounts of warm and cold air admitted. Volume control is effected by regulating the spacing between the dampers so as to limit the number of open apertures or the space in the side wall of the sleeve. In this way, the size of the delivery passage in the sleeve of each-distributing unit is varied in accordance with predetermined operating conditions in the respective distributing units so that air delivery into the air mixing chambers may be maintained substantially equal and constant in all the units.

According to one feature of the invention, the dampers on the plunger are axially movable relative to one another by a suitable motor; for example, in air motor ISpDnsive to static .pressure in the air mixing chamber,

' useable.

2,880,743 ,Patented Apr. 7, :1959

ICC

or responsive 4to airvelocitiesin thevsupply ducts. One of the vdampers is fixed on the lplunger whereas the other lis -slidably carried thereon. The dampers are normally lheld together vby a yieldable member which permits relative movement of the dampers when they are subjected -to forces exceeding a predetermined amount, but which con tinuously urges the dampers to their normal adjacent position.

Another important feature of this invention is damper control in similar or substantially identical distributing units Vfor .delivering equal and constant air volume into every zone of an air distributing unit, even though pressures in the air supply ducts vary at different stations in the system. The dampers of each distributing unit are yspaced fby suitable blocks .in accordance with particular pressure :conditions at the units so as to permit delivery of equal amounts of air into each zone.

These and other objects, features and advantages w-ll become .apparent from the following description and drawings which are merely exemplary to the invention.

ln the drawings:

Figures 1 to 3, inclusive, are fragmentary longitudinal sections of a damper arrangement according to this yinvention, showing `various settings ofthe dampers relative to each other and also showing by full and by broken lines limiting positions of the dampers at each setting;

Figure 4 shows schematically an air vconditioning system embodying another feature of this invention; and

Figure 5 shows a fragmentary longitudinal section of an individual .damper arrangement used in 'Figure -`il.

The damper arrangement shown in the drawings may be used in air distributing units such as illustrated in copending applications, S.N. 106,016, led duly 2l, 1.949, now abandoned or S.N. 203,997, tiled January 2, now Patent No. 2,708,568, granted May -17, 1955.

Referring now more particularly 'to Figures l to '3, inclusive, the air control damper arrangement includes an open-ended sleeve 20 which extends between warm and cold air supply ducts or compartments, shown lin part at 21 and 22, respectively, and which registers at opposite ends with warm air port 23 and cold air port 24. Between its ends sleeve 20 has side wall apertures 25 through which air flows from each supply duct or compartment `into an air mixing chamber, `shown in part at 26.

Flow through side wall apertures 25 is controlled by a pair of axially movable dampers 27 and 28 which -open and close warm air port 21 and cold air port l22, respectively, the axial position of the dampers determining the proportional amounts of warm and cold air admitted. The dampers are mounted on and carried by a reciprocating plunger 29 which is operated by a thermostatically controlled motor (not shown). Preferably, -the motor is operated in accordance with Zone temperatures so that the dampers will be automatically positioned to satisfy the thermostat.

Dampers 27 and 28 are mounted on the plunger between axial spaced abutments 30 and 31, damper 28 being held in fixed relation to the plunger and its adjacent abutment 31 whereas damper 27 is movable axially on the plunger relative to its adjacent abutment 30 and damper 28. The dampers are normally held together by a spring 32. As shown, opposite ends of the spring 32 are anchored in the hubs of dampers 27 and 28, respectively, by axial extensions 33 and 34 which have radially projecting tips fitted into radial grooves 35 and 36 in the respective hubs, other means of holding the spring being other by expandable bellows member 37 which extendsA between and is connected at opposite ends to confronting faces 38 and 39 of the dampers 27 and 28. In the form shown, the hubs of the dampers form the end walls Kof' the bellows, and the ends of the collapsible wall 40 are The dampers are movable relative to one an" fixed in sealed relation to such hubs. Aligned recesses 41 and 42 are provided in the opposing hubs for receiving the bellows wall 40 when the dampers are held in face-toface contact by spring 32.

Bellows 37 communicates through a exible connection 43 and a pipe 44 (shown with a broken end in Fig. 3) with conventional means (not shown) which are responsive to pressure in air mixing chamber 26 so that as static pressure in such chamber increases, the bellows will dilate and separate the dampers 27 and 28, thereby decreasing the number of open apertures in sleeve When the bellows expands, spring 32 yields to permit such damper separation. When static pressure in the mixing chamber decreases, the bellows contracts and releases some or all of the tension in spring 32, thereby allowing the spring to move the dampers towards each other. In this way, the open passage area in the sleeve varies in accordance with mixed air static pressure in air mixing chamber 26 so as to maintain a constant volumetric rate of delivery into the zone being conditioned, the distributing units having fixed apertures into the zone involved. Alternatively, the bellows may be responsive to air velocities in the supply ducts for maintaining such constant volume delivery.

Another form of air flow control is illustrated in Figures 4 and 5 wherein a plurality of air distributing units are shown assembled in an air conditioning system. Conditioned air is delivered to the units under pressure by a supply fan 54 through duct 55, which passes part of the air through a heater 56 and into warm air supply duct 51 and passes the rest of the air through a cooler 57 into cold air supply duct 52. As air passes through the supply ducts, its pressure progressively decreases because of energy losses sustained in overcoming frictional resistance in the ducts.

In Figure 4 the distributing units are partially broken away to show the air control damper arrangements therein for maintaining substantially equal and constant volumetric air delivery into each zone. These damper arrangements are similar to that described in reference to Figures l to 3, inclusive, in that each includes an openended sleeve 58 which registers at opposite ends with warm and cold air inlets 59 and 6i), and which has side wall apertures 61 for pasing air from the respective air inlets into a mixing chamber 62. Each arrangement also includes a pair of dampers 63 and 64 which are mounted for movement together on a single, motor-actuated plunger 66. The dampers are movable axially in sleeve 58 and cooperate with the side wall apertures 61 to proportion the air owing from the warm and cold air inlets into air mixing chamber 62, the position of the dampers on the duct determining the proportional amounts of warm and cold air admitted.

Each damper arrangement may be of the same size and construction, except for damper spacing which is set in accordance with pressure conditions existing in the air supply ducts at each distributing unit. In units near the air source, connecting air supply ducts are rather short and duct pressures are high. However, as the distance between the air distributing unit and air source increases, the air supply ducts are correspondingly longer and air supply duct pressure is correspondingly lower. Accordingly, damper spacing increases as the air supply duct pressures decrease, and elective sleeve length is so varied throughout the air conditioning system that substantially equal and constant volumetric flow is maintained in all the distribtuting units, even though air supply pressures in the system vary from unit to unit.

The dampers 63 and 64 are spaced by a block 65 as clearly shown in Figure 5, the axial length of the block determining the available number of open side wall apertures 61 for passing air from the air supply ducts into the air mixing chamber. Figure 4 shows predetermined damper spacing in a system to obtain substantially equal and constant volumetric ow into all the zones. A relatively long spacer block 65 is disposed between dampers 63 and 64 in air distributing unit 53, which is closest to air supply fan 54, and progressively shorter spacer blocks 65a and 65h are used between the dampers 63 and 64 in air distributing units 53a and 53h, which are successively farther away from the air supply fan 54. In this way the open sleeve passage area is progressively larger as air supply pressures decrease, thereby providing equal volumetric delivery into each zone.

It should be apparent that various details of construction can be changed without departing from the spirit of the invention as defined in the appended claims.

What is claimed is:

1. In a zone air distributing unit for air conditioning apparatus, the combination comprising a casing having a warm air inlet port and a cold air inlet port to admit warm and cold air respectively, a mixed air outlet port to discharge mixed air, an open-ended air flow control duct registering at opposite portions with said warm and cold air inlet ports, said duct having side wall passage means along its length to pass conditioned air from said inlet ports to said air mixing chamber, a pair of dampers movable in the duct along the length of said side wall passage means, one of said dampers opening and closing said warm air inlet port and the other damper opening and closing said cold air inlet port, means moving said dampers conjointly so that as one port opens the other closes, movable means connected with said dampers to vary the spacing between said dampers, and means to activate and inactivate automatically the movable means when flow through said side wall passage means varies so as to vary the size of open area in the side wall passage means and to maintain constant volume delivery into the zone.

2. In a zone air distributing unit for air conditioning apparatus, the combination comprising a casing having a warm air inlet port and a cold air inlet port to admit warm and cold air respectively, a mixed air outlet port to discharge mixed air, an open-ended air ilow control duct registering at opposite ends with said warm and cold air inlet ports, said duct having side wall pasage means along its length to pass conditioned air from said inlet ports to said air mixing chamber, a pair of dampers in the duct movable along the length of said side wall passage means, one of said dampers opening and closing said warm air inlet port and the other damper opening and closing said cold air inlet port, means moving said dampers conjointly so that as one port opens the other closes, means dening a fluid pressure chamber between said dampers, and yieldable means of predetermined strength normally holding said dampers in predetermined longitudinal positions relative to each other, but responsive to changing uid pressures within the chamber acting on confronting damper faces to allow axial movement of the dampers away from each other, thereby limiting the size of open area in the side wall passage means and maintaining constant volume delivery into the zone.

3. In a zone air distributing unit for air conditioning apparatus, the combination comprising a casing having a warm air inlet port and a cold air inlet port to admit warm and cold air respectively, an air mixing chamber, an open-ended air flow control duct registering at opposite ends with said warm and cold air inlet ports, said duct having side wall passage means along its length to pass conditioned air from said inlet ports to said air mixing chamber, a mixed air outlet in said chamber to discharge mixed air, a pair of `dampers movable in the duct along the length of said side wall passage means, one of said dampers opening and closing said warm. air inlet port and the other damper opening and closing said cold air inlet port, means moving said dampers conjointly so that as one port opens the other closes, means defining a lluid pressure chamber between said dampers, and yieldable means of predetermined strength normally holding said dampers in predetermined longitudinal positions relative to each other, but responsive to changing fluid pressures in the chamber acting on confronting damper faces to allow axial movement of the dampers away from each other, said fluid pressure chamber communicating with said air mixing chamber so that as the pressure in the air mixing chamber varies the dampers will be automatically spaced to vary the size of open area in the side wall passage means and to maintain constant volume delivery into the air mixing chamber.

4. An air conditioning apparatus for conditioning a plurality of separate zones, the combination including centrally located air conditioning means, air distributing means in each zone, cold air and warm air supply ducts connecting said central conditioning means with said air distributing means for supplying Warm and cold air thereto, means forcing air under pressure through both air supply ducts, and air volume control means in the air distributing means set in accordance with air supply pressures at their respective zones 'for admitting substantially equal air volume into every zone.

5. An air conditioning apparatus in accordance with claim 4 in which said air volume control means includes a warm air inlet port and a cold air inlet port, a mixed air outlet port to discharge mixed air, a duct extending between and having opposite ends registering with said warm and cold air inlet ports, said duct having side wall passage means along its length to pass warm and cold air from said inlet ports to said mixed air outlet port, a pair of dampers movable conjointly in said duct along said side Wall passage means, one of said dampers opening and closing said Warm air inlet port and the other damper opening and closing said cold air inlet port, and removable spacer block means interposed between the dampers to space said dampers longitudinally so as to limit the size of the open area in said side wall passage means for providing predetermined volume delivery into the respective zones in accordance with the air supply pressures at the respective zones.

References Cited in the tile of this patent UNITED STATES PATENTS 2,083,159 Roe June 8, 1937 2,194,694 Denker Mar. 26, 1940 2,440,052 Lingen et al Apr. 20, 1948 2,584,420 Bronson Feb. 5, 1952 2,669,248 Miller Feb. 16, 1954 2,720,150 Lyman Oct. 11, 1955 2,720,151 Kreuttner Oct. 11, 1955 2,759,490 Phillips et al Aug. 21, 1956 

